International Nuclear Information System (INIS)

Electron paramagnetic resonance (EPR), optical, infrared and Raman spectral studies have been carried out on vanadyl ions doped in polyvinylalcohol (PVA) films. The spin-Hamiltonian parameters (g and A) and the molecular orbital coefficients (#beta#_2"*"2 and k) have been evaluated. The values of spin-Hamiltonian parameters confirm that the vanadyl ions are present in PVA films as VO"2"+ molecular ions in an octahedral site with a tetragonal compression (C_4_v). The temperature variation EPR studies reveal that the variation of number of spins with temperature is in accordance with Boltzmann law. It is interesting to observe that the variation of susceptibility with temperature obeys Curie-Weiss law. The FT-IR and FT-Raman spectrum exhibits few bands, which are attributed to O-H, C-H, C-C and C-O groups of stretching and bending vibrations. The optical absorption spectrum exhibits ...

Science.gov (United States)

We discuss how magnetic phenomena affect superconductivity in simple metals, transition metals and alloys thereof, and dilute Rare-Earth alloys. It is shown both qualitatively and quantitatively that superconductors are sensitive probes for studying itinerant spin excitations, local spin excitations associated with nearly magnetic impurities, the effect of the atomic environment on the stability of local magnetic moments, and the nature of the spin order in Rare-Earth alloys. Also, we discuss how magnetic impurities can be used to study the electronic configuration which is responsible for superconductivity in Laves-phase crystals like A-15 compounds and ..beta..-W crystals, for example.

International Nuclear Information System (INIS)

Magnetic excitation in coupled multispin system is studied theoretically focusing on Cu_2Fe_2Ge_4O_1_3 and Cu_2CdB_2O_6 as typical examples of such system. These compounds consist of spin dimer and spin monomer parts and show an antiferromagnetic phase transition at low temperatures due to the spin monomer part. A multispin containing a spin dimer and spin monomers is treated as a basis unit. The multispin forms a spin multiplet and its energy levels are separated into high and low regions reflecting the characteristic energies of the dimer and monomer parts. We regard the system as interacting multispins and apply an extended Holstein-Primakoff theory by introducing bosons for each energy level of a spin multiplet. In the low-energy region, the obtained magnon dispersion and dynamical spin correlation function agree ...

Energy Technology Data Exchange (ETDEWEB)

In this Brief Report, we consider dijet production at {gamma}{gamma} colliders as a probe of recently proposed, large extra-dimensional gravity models. The exchange of virtual, spin-2 graviton towers (Kaluza-Klein excitations) significantly modifies the cross section, as compared to the standard model predictions. We find that, in order to maximize the value of the effective scale that can be probed at a given center-of-mass energy, a very severe p{sub T} cut should be applied; in general, a p{sub T} equal to approximately 46% of the e{sup +}e{sup -} beam energy gives the highest reach. We find that we can probe the effective mass scale from about 2.7 TeV to 11.1 TeV, depending on the center-of-mass energy and assumptions about the model. (c) 2000 The American Physical Society.

Energy Technology Data Exchange (ETDEWEB)

For the first time in scientific literature, in our joint work with Dr. G. Ladwig in 1978 it was established phase portraite of the oxide vanadium-phosphorus system within wide range of P/V ratios from 0.5 to 3.2. Some later those data were confirmed. By investigation of the properties of individual vanadium-phosphorus phases it was also shown that the active component of such catalysts in n-butane oxidation was vanadyl pyrophosphate phase (VO){sub 2}Pr{sub 2}O{sub 7}. From then the conclusion has been evidenced by numerous publications and at present it has been out of doubt practically all over the world. It was hypothized that the unique properties of (VO){sub 2}P{sub 2}O{sub 7} in the reaction of n-butane oxidation could be explained by the presence of paired vanadyl groups and nearness of the distances between neighbouring vanadyl pairs and that between the first and fourth carbon atoms in n-butane molecule. The ...

British Library Electronic Table of Contents (United Kingdom)

The detection and characterization of deeply buried fatigue damage in thick, multi-layer airframe components pose significant technical challenges to the aviation safety community. Currently, no nondestructive evaluation technique is available to reliably detect such potential damage from the exterior of the airframe, which is highly desirable in light of inspection cost as well as avoidance of structure damage. Recent technological advances in high-sensitivity magnetic sensors, i.e., spin-dependent tunneling (SDT) sensors, make it feasible to employ electromagnetic inspection techniques for deep fatigue crack inspection. In this work, we report on the development and fabrication of a low frequency eddy current probe based on a magnetically shielded SDT pickup sensor concentrically located...

CERN Document Server

We consider a holographic description of a system of strongly-coupled fermions in 2+1 dimensions based on a D7-brane probe in the background of D3-branes. The black hole embedding represents a Fermi-like liquid. We study the excitations of the Fermi liquid system. Above a critical density which depends on the temperature, the system becomes unstable towards an inhomogeneous modulated phase which is similar to a charge density and spin wave state. The essence of this instability can be effectively described by a Maxwell-axion theory with a background electric field. We also consider the fate of zero sound at non-zero temperature.

International Nuclear Information System (INIS)

The emission of #alpha# particles in coincidence with the most deeply inelastic heavy-ion reactions has been studied for "1"8"1Ta + "1"6"5Ho at 1354 MeV laboratory energy and /sup nat/Ag + "8"4Kr at 664 MeV. #alpha# particle energy spectra and angular distributions, in coincidence with a projectile-like fragment, were acquired both in the reaction plane and out of the reaction plane at a fixed in-plane angle. The in-plane data for both systems are employed to show that the bulk of the #alpha# particles in coincidence with the deep-inelastic exit channel can be explained by evaporation from the fully accelerated fragments. Average velocity diagrams, #alpha#-particle energy spectra as a function of angle in several rest frames, and #alpha#-particle angular distributions are presented. The out-of-plane #alpha# particle angular distributions and the #gamma#-ray multiplicities are used to study the transfer and partitioning of angular momentum between the two fragments. For the /sup nat/Ag ...

J-STORE (Japan)

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UK PubMed Central (United Kingdom)

Electron spin resonance (ESR) studies have been performed on spin-labeled model membranes aligned using the isopotential spin-dry ultracentrifugation (ISDU) method of Clark and Rothschild. This method...Full Text Available

Energy Technology Data Exchange (ETDEWEB)

X-ray magnetic circular dichroism (XMCD) was used to probe the existence of induced magnetic moments in yttrium iron garnet (YIG) films in which yttrium is partly substituted with lanthanum, lutetium or bismuth. Spin polarization of the 4d states of yttrium and of the 5d states of lanthanum or lutetium was clearly demonstrated. Angular momentum resolved d-DOS of yttrium and lanthanun was shown to be split by the crystal field, the two resolved substructures having opposite magnetic polarization. The existence of a weak orbital moment involving the 6p states of bismuth was definitely established with the detection of a small XMCD signal at the Bi M{sub 1}-edge. Difference spectra also enhanced the visibility of subtle changes in the Fe K-edge XMCD spectra of YIG and {l_brace}Y, Bi{r_brace}IG films. Weak natural X-ray linear dichroism signatures were systematically observed with all iron garnet films and with a bulk YIG single crystal cut ...

KoreaScience (Korea)

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International Nuclear Information System (INIS)

Ionic motion of a divalent cation, Ba"2"+, in a single crystal of Ba-Al-priderite was studied using "2"7Al as an NMR probe. Several pairs of satellite peaks due to electric quadrupole interaction were observed superposed on broad satellite tails on both sides of the main peak of "2"7Al. These peak pairs indicate the existence of some stable three-dimensional configurations of Ba"2"+ ions in the structure, and the broad shoulders show a random substitution of Al"3"+ for Ti"4"+ sites. The temperature dependence of the spin-lattice relaxation time T"*_l measured in the temperature range from 161 to 1176 K was analyzed by a curve fitting method on the assumption that there are two types of Ba"2"+ ions. An activation energy of 0.47 eV was obtained for the motion of Ba"2"+ ions which are easy to move, and a broad distribution of activation energies spread over a range from 0.95 to 2.45 eV was obtained for the motion of Ba"2"+ ions which form a ...

Science.gov (United States)

Not Available

Science.gov (United States)

... Accession Number : ADD321199. Title : OPTIMIZATION OF EDDY CURRENT PROBES FOR NDT OF CARBON FIBER COMPOSITES. ...

Science.gov (United States)

... Accession Number : ADD335809. Title : Characterization of Absolute-Resonant Eddy Current Probes,. Corporate Author : ...

International Nuclear Information System (INIS)

Transparent aluminum doped zinc oxide (ZnO:Al, AZO) conducting thin films with a high-preferential c-axis orientation were synthesized using a new sol-gel formula. The films were deposited using a spin-coating route onto borosilicate glass substrates. We used propylene glycol methyl ether (PGME) as the solvent in place of ethylene glycol monomethyl ether (EGME), which is commonly used because it is easier to deposit onto the substrates. PGME is also superior in terms of health and safety. PGME solvent does not need to settle for several days before use and can be spin-coated as soon as the raw material and solvent are mixed. The effects of this novel solvent on the structural, morphological, electrical and optical properties are discussed using XRD, SEM, a four-point probe and UV-VIS spectrophotometry. It was found that the films produced with PGME showed a high-preferential c-axis orientation and compact microstructure in ...

International Nuclear Information System (INIS)

We evaluate the neutrino fluxes to be expected from neutralino lightest supersymmetric particle (LSP) annihilations inside the Sun, within the minimal supersymmetric extension of the standard model with supersymmetry-breaking scalar and gaugino masses constrained to be universal at the grand unified theory scale [the constrained minimal supersymmetric standard model (CMSSM)]. We find that there are large regions of typical CMSSM (m_1_/_2,m_0) planes where the LSP density inside the Sun is not in equilibrium, so that the annihilation rate may be far below the capture rate. We show that neutrino fluxes are dependent on the solar model at the 20% level, and adopt the AGSS09 model of Serenelli et al. for our detailed studies. We find that there are large regions of the CMSSM (m_1_/_2,m_0) planes where the capture rate is not dominated by spin-dependent LSP-proton scattering, e.g., at large m_1_/_2 along the CMSSM coannihilation strip. We calculate neutrino fluxes above ...

Energy Technology Data Exchange (ETDEWEB)

We consider Rashba spin-orbit effects on spin transport driven by an electric field in semiconductor quantum wells. We derive spin diffusion equations that are valid when the mean free path and the Rashba spin-orbit interaction vary on length scales larger than the mean free path in the weak spin-orbit coupling limit. From these general diffusion equations, we derive boundary conditions between regions of different spin-orbit couplings. We show that spin injection is feasible when the electric field is perpendicular to the boundary between two regions. When the electric field is parallel to the boundary, spin injection only occurs when the mean free path changes within the boundary, in agreement with the recent work by Tserkovnyak et al (Preprint cond-mat/0610190)

Energy Technology Data Exchange (ETDEWEB)

Nuclear steam generator tubes have become flawed in ways that challenge conventional eddy current probes. In response to the shortcomings of conventional probes, array probes have been developed to improve measurement capabilities. However, the commercially available array probes have exhibited several weaknesses that offset the advantages and limit the applications in steam generator inspections. A primary weakness is the relatively high rate of probe failure coupled with the high unit cost for each probe. This can be costly for a utility in the time lost for probe replacement and increased radiation exposure in addition to the probe costs. Other weaknesses which make array probes undesirable for routine use are: poor mechanical and electrical characteristics; difficulty in operation and ...

Energy Technology Data Exchange (ETDEWEB)

Doubly decoupled structures in doubly odd deformed nuclei are reexamined and shown to be composed of a pseudo-spin aligned neutron and a decoupled proton. (orig.).

UK PubMed Central (United Kingdom)

A multiple probe approach of implanting microdialysis probes into each separate tissue layer would better represent sampling from the stomach. Presently, microdialysis sampling experiments are...Full Text Available

Energy Technology Data Exchange (ETDEWEB)

We analyze spin correlations between top quark and anti-top quark produced at polarized e{sup +} e{sup -} and {gamma}{gamma} colliders. We consider a generic spin basis to find a strong spin correlation. Optimal spin decompositions for top quark pair are presented for e{sup +}e{sup -} and {gamma}{gamma} colliders. We show the cross- section in these bases and discuss the characteristics of results.

International Nuclear Information System (INIS)

... electron spin resonance gamma radiation lipids lyophilization lysozyme radicals

Energy Technology Data Exchange (ETDEWEB)

The linearized collective Schroedinger equation for nuclear quadrupole surface vibrations incorporates a new spin degree of freeedom with a spin value of 3/2. We use this equation to describe the low energy spectrum of certain even-odd Ir nuclei which have a spin 3/2 in their ground state. For that purpose we explicitly introduce collective spin-dependent potentials which simulate the interaction of the valence nucleon with the core. The linearized Schroedinger equation is transformed into an effective Schroedinger equation with collective spin-dependent potentials. Already collective spin-orbit couplings of SO(3) and SO(5) type are sufficient to reproduce the lowest excited states of even-odd Ir nuclei. (orig.).

CERN Document Server

The junction conditions for General Relativity in the presence of domain walls with intrinsic spin are derived in three and higher dimensions. A stress tensor and a spin current can be defined just by requiring the existence of a well defined volume element instead of an induced metric, so as to allow for generic torsion sources. In general, when the torsion is localized on the domain wall, it is necessary to relax the continuity of the tangential components of the vielbein. In fact it is found that the spin current is proportional to the jump in the vielbein and the stress-energy tensor is proportional to the jump in the spin connection. The consistency of the junction conditions implies a constraint between the direction of flow of energy and the orientation of the spin. As an application, we derive the circularly symmetric solutions for both the rotating string with tension and ...

Energy Technology Data Exchange (ETDEWEB)

In this report, I surveyed physics potential of the {gamma}{gamma} option of a linear e{sup +}e{sup -} collider with the following questions in mind: What new discovery can be expected at a {gamma}{gamma} collider in addition to what will be learned at its 'parent' e{sup +}e{sup -} linear collider? By taking account of the hard energy spectrum and polarization of colliding photons, produced by Compton back-scattering of laser light off incoming e{sup -} beams, we find that a {gamma}{gamma} collider is most powerful when new physics appears in the neutral spin-zero channel at an invariant mass below about 80% of the c.m. energy of the colliding e{sup -}e{sup -} system. If a light Higgs boson exists, its properties can be studied in detail, and if its heavier partners or a heavy Higgs boson exists in the above mass range, they may be discovered at a {gamma}{gamma} collider. CP property of the scalar sector can be explored in detail by making use of ...

International Nuclear Information System (INIS)

The average single-particle field shows a very small pseudo-spin-orbit splitting in the pseudo-spin representation. If this splitting is neglected, pseudo-spin becomes a good quantum number and the resulting scheme (the pseudo-Nilsson model) has a very simple interpretation. The pseudo-spin symmetry embodied in the realistic deformed average field is explored by comparing the single-particle energies and wave functions of the deformed Woods-Saxon model with the corresponding results of the pseudo-Nilsson model. The scheme is used to calculate the magnetic moments of deformed odd-A nuclei of the rare-earth region. (orig.).

Science.gov (United States)

Not Available

Energy Technology Data Exchange (ETDEWEB)

Described herein is an optical probe (120) for use in characterizing surface defects in wafers, such as semiconductor wafers. The optical probe (120) detects laser light reflected from the surface (124) of the wafer (106) within various ranges of angles. Characteristics of defects in the surface (124) of the wafer (106) are determined based on the amount of reflected laser light detected in each of the ranges of angles. Additionally, a wafer characterization system (100) is described that includes the described optical probe (120).

Energy Technology Data Exchange (ETDEWEB)

Short communication.

Science.gov (United States)

Not Available

Energy Technology Data Exchange (ETDEWEB)

This paper described the application of an AC surface probe, similar to presently used eddy current probes, to the measurement of DC transport critical currents and critical state dissipation in high {Tc} superconductors. It has been shown that the probe can provide quantitative measurement of the full field penetration in superconducting samples by measuring the response of AC induced screening currents for superconducting materials in the form of tapes with overlayers of silver. In this manner, the AC probe can be used to replace the contact DC probe for determining critical currents in a noncontacting and local manner suitable for scanning over or along the sample.

Energy Technology Data Exchange (ETDEWEB)

This paper described the application of an AC surface probe, similar to presently used eddy current probes, to the measurement of DC transport critical currents and critical state dissipation in high [Tc] superconductors. It has been shown that the probe can provide quantitative measurement of the full field penetration in superconducting samples by measuring the response of AC induced screening currents for superconducting materials in the form of tapes with overlayers of silver. In this manner, the AC probe can be used to replace the contact DC probe for determining critical currents in a noncontacting and local manner suitable for scanning over or along the sample.

Energy Technology Data Exchange (ETDEWEB)

The spin relaxation processes within the pyrochlore Ho{sub 2}Ru{sub 2}O{sub 7} have been investigated by neutron scattering and bulk property techniques. A single-ion process, that is thermally activated, dominates the spin-spin relaxation spectrum above 2 K. Assuming Arrhenius behaviour, we found an activation energy {delta} = (329 {+-} 6) K and characteristic relaxation time {tau}{sub 0} (5.2 {+-} 0.3) x 10{sup -12} s in the paramagnetic state, akin to those found in the spin ice, Ho{sub 2}Ti{sub 2}O{sub 7}. Atlow temperature (T<95 K) the activation energy lowers and below 20 K the entropy and ac susceptibility are similar to that observed in other spin ice compounds within a 10 kOe field.

International Nuclear Information System (INIS)

Computer programs have been developed for modelling impedance and transmit-receive eddy current probes in two-dimensional axis-symmetric configurations. These programs, which are based on analytic equations, simulate bobbin probes in infinitely long tubes and surface probes on plates. They calculate probe signal due to uniform variations in conductor thickness, resistivity and permeability. These signals depend on probe design and frequency. A finite element numerical program has been procured to calculate magnetic permeability in non-linear ferromagnetic materials. Permeability values from these calculations can be incorporated into the above analytic programs to predict signals from eddy current probes with permanent magnets in ferromagnetic tubes. These programs were used to test various probe designs for new testing applications. ...

UK PubMed Central (United Kingdom)

Spin-lattice relaxation rates of protein and water protons in dry and hydrated immobilized bovine serum albumin were measured in the range of ¹H Larmor frequency from 10 kHz to 30...Full Text Available

International Nuclear Information System (INIS)

The Schroedinger equation for nuclear quadruple surface vibrations is linearized with the consequence that a new spin degree of freedom appears in the wave function of the linearized equation. This spin is called collective spin and has a value of 3/2. The linearized Schroedinger equation for quadrupole vibrations is used for the description of certain collective aspects of even-odd "1"8"7","1"8"9","1"9"1Ir nuclei which have a spin 3/2 in their ground state. As a potential we use the #gamma#-soft collective potential of the neighboring even-even nuclei, which is inserted into the linearized Schroedinger equation via a scalar coupling. This leads to a collective spin-dependent fine structure splitting of the energy levels governed by a collective SO(5) spin-orbit coupling and a correction to the kinetic energy. Further, we consider explicitly ...

UK PubMed Central (United Kingdom)

Measurement of intrathylakoid aqueous volumes by electron spin resonance spectroscopy was used to study ionic permeability properties of thylakoid membranes isolated from Beta vulgaris...Full Text Available

Energy Technology Data Exchange (ETDEWEB)

Conventional eddy current bobbin probes are known to be ineffectual in detecting circumferential cracks in tubing. Multi-pancake and/or rotating pancake probes are required to detect circumferential cracks. It has recently been demonstrated in CANDU steam generator tubes, with deformation, ferromagnetic deposits, and copper deposits, that multi-channel probes with transmit-receive (T/R) coils are superior to those using surface impedance coils. Unlike rotating probes, the design of a new probe denoted as C3 permits fast, single-scan inspection of a full-length tube at inspection speeds comparable to conventional bobbin probes. Since 1992, the probe has been used routinely for steam generator in-service inspection at 4 CANDU plants. Defective tubes have been plugged and the units returned to service, and they continue to operate without ...

International Nuclear Information System (INIS)

For spintronic applications it is important to establish how efficiently spins can be injected from a magnetic material into a non-magnetic material and the distance over which those spins survive. It is thought that spin polarised transport current can be determined by using the suppression of the Andreev reflection between a superconductor and the spin polarised material (Science 282 (1998) 85). Cu/Co bilayers are potentially an ideal test system for such study. In this paper we assess the feasibility of using point contact Andreev reflection spectroscopy to address this problem using a superconducting niobium tip at 4.2 K.

Energy Technology Data Exchange (ETDEWEB)

We have investigated the effect of the rho tensor coupling on binding energies, matter root-mean-square radii and spin orbit splittings of Ca isotopes in the relativistic mean-field theory with sigma, omega, and rho mesons. It is shown that binding energies and matter root-mean-square radii are insensitive to an alteration in the strength of the rho tensor coupling and an explanation of this is given. We have further shown that inclusion of the rho tensor coupling will give isospin-dependent spin-orbit splittings and this will greatly affect spin-orbit splittings of nuclei near the neutron drip line. (author). Letter-to-the-editor.

CERN Document Server

The study of randomness in low-dimensional quantum antiferromagnets is at the forefront of research in the field of strongly correlated electron systems, yet there have been relatively few experimental model systems. Complementary neutron scattering and numerical experiments demonstrate that the spin-diluted Heisenberg antiferromagnet La2Cu(1-z)(Zn,Mg)zO4 is an excellent model material for square-lattice site percolation in the extreme quantum limit of spin one-half. Measurements of the ordered moment and spin correlations provide important quantitative information for tests of theories for this complex quantum-impurity problem.

International Nuclear Information System (INIS)

We discuss polarizing a proton beam in a storage ring, either by selective removal or by spin flip of the stored ions. Prompted by recent, conflicting calculations, we have carried out a measurement of the spin-flip cross section in low-energy electron-proton scattering. The experiment uses the cooling electron beam at COSY as an electron target. The measured cross sections are too small for making spin flip a viable tool in polarizing a stored beam. This invalidates a recent proposal to use co-moving polarized positrons to polarize a stored antiproton beam.

International Nuclear Information System (INIS)

... spin-lattice relaxation angular momentum electronic circuits magnetic

KoreaScience (Korea)

Full Text Available

Energy Technology Data Exchange (ETDEWEB)

The spin-up problem of He II in a cylindrical container of infinite and finite height is considered on the basis of the Hall-Vinen-Bekarevich-Khalatnikov equations. The boundary conditions include the assumption of the generation of superfluid vorticity at the walls of the container. In the lowest order approximation with respect to viscosity, the problem is reduced to a Stefan problem for a single diffusion-type equation. Examples of solutions are given which show that the method used gives a good insight into the physical development of the spin-up flow.

Energy Technology Data Exchange (ETDEWEB)

Lorentz invariant theory of second quantization of superluminal electromagnetic fields has been constructed in purely group theoretical manner by using the reduced expansion of four-vector fields for imaginary mass system in terms of standard helicity representations of Poincare group. It has been shown that the usual relationship of spin and statistics need not be inverted for Lorentz invariance of the theory of spin-1 tachyons. 15 refs.

Energy Technology Data Exchange (ETDEWEB)

Results are reported in the areas of: chiral fermions and anomalies, superstring finiteness, superstring phenomenology, spin splittings in heavy quarkonia, low-energy limits of superstring, a supersymmetric electroweak model with a light squark, scalar quark bound states, fermionic tachyons and Poincare representations, relativistic dynamics of spin-one particles and deuteron-nucleus scattering, interactions involving higher spin massless particles, and classical action at a distance theories which contain a cutoff. (LEW)

UK PubMed Central (United Kingdom)

Synthetic oligoribonucleotides have been used to probe the interaction of MS2 coat protein with the translational operator of the MS2 replicase gene. We have investigated the possible formation of a...Full Text Available

UK PubMed Central (United Kingdom)

A commercially available synthetic nucleic acid probe (SNAP) conjugated to alkaline phosphatase was compared with standard culture techniques for detecting Campylobacter species. The SNAP was able to...Full Text Available

UK PubMed Central (United Kingdom)

A new gadolinium chelating NIR fluorescent molecular probe increases T₁ relaxivity of water protons, facilitating combined optical and magnetic resonance imaging.

Energy Technology Data Exchange (ETDEWEB)

CANDU steam generators and heat exchangers have been afflicted with a significant variety of degradation mechanisms. Until recently, detection and characterization of most of the varieties of flaws required usage of several different eddy current techniques. Tubes needed to be scanned multiple times to ensure they were inspected for all possible degradation mechanisms. The time required to deploy so many different types of techniques to inspect the steam generator tubes has had a significant impact on the inspection schedules. The X-Probe was designed with an array of eddy current coils capable of detecting, characterizing and sizing axial, circumferential and volumetric flaws. The X-Probe is a fast-scanning probe with scanning speed equivalent to speeds typically used for simple bobbin coil probes. With its capability of fulfilling most if not all of the functions of the other tube-testing eddy current ...

Energy Technology Data Exchange (ETDEWEB)

This paper describes the technical design and performance of the diagnostic system installed in the tokamak TCABR to measure parameters of the plasma edge. The system consists of four Langmuir probes under remote control. (author)

UK PubMed Central (United Kingdom)

The utility of a two-photon optical fiber fluorescence probe (TPOFF) for sensing and quantifying tumor fluorescent signals was tested in vivo. Xenograft tumors were developed in athymic mice using MCA207...Full Text Available

ScienceCinema

...of this article he quotes um i am told by my english ...

Energy Technology Data Exchange (ETDEWEB)

This paper describes a signal simulator which is designed to calibrate eddy current probes. By using simultaneously an excitation coil and an electrically conducting plane, the simulator can emulate signals which correspond to spot welds with different flaws. The presence of a conducting plane allows a wide variation of the amplitude and phase of the excitation coil voltage during the calibration of a probe. A mathematical model for the simulator is derived and used to study the variation of the impedance change upon the parameters of the probe. Numerical computation shows that the impedance change depends in an important way on the frequency of the excitation coil current.

Science.gov (United States)

... Accession Number : ADD323869. Title : EFFECTS OF SHIELDING ON PROPERTIES OF EDDY CURRENT PROBES WITH FERRITE CUP CORES. ...

Energy Technology Data Exchange (ETDEWEB)

Here the authors try to dissolve some commonly held misconceptions about the operation of eddy current probes used for inspecting heat exchanger tubes. With the help of computer model results, the authors demonstrate that, for optimized operation, absolute/differential probes should be operated with coil current flowing in phase with another. This month's feature should be of interest to researchers as well as for NDT field personnel.

International Nuclear Information System (INIS)

To overcome the limitations of conventional bobbin style eddy-current probes, it has become common practice to perform some portion of a steam generator tube inspection program with array coil probes. Typically, eight surface-riding pancake coils are utilized in a probe head, either as eight independent coils (8 x 1) or in a parallel combination of four serially connected coils (4 x 4). The advantages of the array coils are improved sensitivity to intergranular attack (IGA), reduced interference from tube denting, and improved sensitivity to circumferential cracking. The current status of commercially available probes is such that several weaknesses in array coils have limited the widespread application of this technology. Task S 301-6 was conceived to address each of the weaknesses in order to produce a more reliable and cost-effective probe. The emphasis was on reliability, since ...

Energy Technology Data Exchange (ETDEWEB)

The effects of spin diffusion on the free induction decay (FID) of protons associated with the noncrystalline domains of two polymers, polyethylene and blended Nylon 66 (ZYTEL-408), have been examined using Goldman--Shen NMR pulse sequence ((1/2)..pi..x-t/sub 0/-(1/2)..pi..x-bar-tau-(1/2)..pi..x-t). At tau< or approx. =100 ..mu..s, the FID is drastically distorted from the exponential form while at longer tau(tau> or approx. =500 ..mu..s) an exponential FID is observed; but its transverse spin relaxation rate is smaller than that of the FID obtained after a single (1/2)..pi..x pulse and approaches this value at the limit of large tau. These findings are interpreted in terms of the theory of rapid spin diffusion. The spatial variation in the spin relaxation rate within the noncrystalline domain is inferred.

CERN Document Server

Starting from the Plebanski formulation of gravity as a constrained BF theory we propose a new spin foam model for 4d Riemmanian quantum gravity that generalises the well-known model of Barrett-Crane and resolves the ultralocality problem that this model is known to possess. It is well known that the BF formulation of 4d gravity possesses two sectors: one corresponding to gravity and the other topological. The model presented here is shown to give a quantisation of the gravitational sector. The present model is dual to the recently proposed spin foam model of Engle et al. which, we show, corresponds to the topological sector of the theory. One important outcome of our approach is that it also allow us to introduce the Immirzi parameter into the framework of spin foam quantisation. We generalize some of our considerations to the Lorentzian setting and obtain a new spin foam model in that context as well.

International Nuclear Information System (INIS)

We theoretically model a nuclear-state preparation scheme that increases the coherence time of a two-spin qubit in a double quantum dot. The two-electron system is tuned repeatedly across a singlet-triplet level-anticrossing with alternating slow and rapid sweeps of an external bias voltage. Using a Landau-Zener-Stueckelberg model, we find that in addition to a small nuclear polarization that weakly affects the electron spin coherence, the slow sweeps are only partially adiabatic and lead to a weak nuclear spin measurement and a nuclear-state narrowing which prolongs the electron spin coherence. This resolves some open problems brought up by a recent experiment. We also show that the electronic two-spin states singlet and triplet T_+ are promising candidates for the implementation of a qubit in GaAs double quantum dots (DQD). A coherent superposition of the ...

Energy Technology Data Exchange (ETDEWEB)

This paper presents a mathematical model that calculates eddy current signals from laterally spaced transmit-receive pancake coils. This model was validated by comparing calculations with laboratory measurements and it has been applied to evaluating design variations in X-Probe eddy current array coils. This model was used to quantify detection capabilities of probe designs with different numbers of coils. The current standard X-Probe design for 13 mm (0.5 inch) diameter steam generator tubes uses 3 rows of coils with 8 coils per row. This design is commonly referred to as the '8 coil X-Probe'. A significant improvement in detection capability was predicted for an X-Probe with 12 coils per row (called the '12 coil X-Probe') detecting short circumferential crack-like flaws. Based on these calculations, a prototype 12 coil ...

International Nuclear Information System (INIS)

The bobbin probe technique is basically one of the important ECT methods for the steam generator tube integrity assessment that is practiced during each plant outage. The bobbin probe also is the essential component which consists of the whole ECT examination system, and provides a decisive data for the evaluation of tube integrity in compliance with acceptance criteria described in specific procedures. The selection of probe is especially important because the quality of acquired ECT data is determined by the probe design characteristics, such as geometry and operation frequency, and has an important effect on examination results. The Electric Power Research Institute (EPRI) has recently defined the procedures for the qualification of eddy current hardware and technique. These procedures provide two basic methods for qualification. Flawed tube removed from operation, or artificial flaw is required for ...

Energy Technology Data Exchange (ETDEWEB)

Five corrosion probes were received from West Valley Nuclear Services for evaluation in simulated tank 8D-2 3rd-stage sludge wash slurry. The same waste slurry simulated was also used in a series of ongoing corrosion studies assessing the effects of in-tank sludge washing on the integrity of tank 8D-2. Two of the corrosion probes were installed in the coupon corrosion test vessels operating at {approximately}150{degrees}F to compare performance of the probes with that observed by coupon tests conducted in the same vessels. Corrosion rate data calculated from electrical resistance measurements of the corrosion probes were evaluated for this study using two slightly different approaches. One approach uses the total length of exposure of the probe to give a ``time-averaged`` value of the corrosion rate. The other approach uses a shorter period of time (relative to the length of the ...

Energy Technology Data Exchange (ETDEWEB)

The Electromagnetic Fluctuations (EMF) diagnostic will be used to monitor ion fluctuations which could be unstable in MFTF-B. Each probe assembly includes a high impedance electrostatic probe to measure potential fluctuations, and a group of nested, single turn loops to measure magnetic fluctuations in three directions. Eventually, more probes and loops will be added to each probe assembly for making more detailed measurements. The sensors must lie physically close to the plasma edge and are radially positionable. Also, probes at separate axial locations can be positioned to connect along the same magnetic field line. These probes are similar in concept to the rf probes used on TMX, but the high thermal load for 30-second shots on MFTF-B requires a water-cooled design along with temperature monitors. Each signal channel has a bandwidth of ...

Energy Technology Data Exchange (ETDEWEB)

We treat symmetric semi-infinite nuclear matter in the relativistic mean-field approximation for the scalar-vector field theoretical model. Using special-type Dirac spinors the nucleonic Dirac equation is decoupled into two sets of differential equations for the spin-orientation dependent orbital nucleon Dirac spinors. We also rewrite the Dirac equation in terms of second-order differential equations with the spin-orbit interaction appearing explicitly. These equations can be solved if the spin-orbit part is left out. The spin-orbit effects thus can be isolated, and are shown to reduce the surface energy coefficient a/sub s/ as well as the surface thickness t in such a way that their ratio remains practically unchanged. For realistic lagrangians - in linear as well as non-linear forms - consistent with the empirical spin-orbit single-partial level splittings, a/sub s/ is reduced by ...

International Nuclear Information System (INIS)

Angelin Pedra is a specie found in the north of Mato Grosso State in Brazil, where an expressive volume of waste of this wood is produced. An alternative to recycle this waste is to produce wood plastic composites. However, structural and chemical investigations are fundamental to generate information for this use. In the present work, low field NMR was used to determine the spin-lattice and spin-spin relaxation times with objective to investigate the molecular dynamic behavior of the alburnu and cerne regions of Angelin Pedra aiming at a potential use of this waste wood in polymeric composites. The results of the proton spin-lattice relaxation time (T1H) and the proton spin-spin relaxation time (T2H) showed at least three different mobility domains for both regions. Among the values, one was very flexible and other was rigid. Knowing that wood is a polymer composite basically constituted by cellulose, ...

International Nuclear Information System (INIS)

In terms of Berezins's theory of symbols of operators, the integral formulation is suggested for the free differential algebra which gives rise to consistent equations of motion of interacting massless fields of all spins 0#<=#s<#infinity# in the frameworks of gravity. In the first nontrivial order of the expansion in powers of curvatures, Frobenius consistency conditions for higher-spin equations of motion are shown to reduce to the simple geometrical fast that there are two ways for splitting any quadrangle in two triangles. To clarify our construction, we illustrate how it works in the simplest case of pure gravity. (orig.).

CERN Document Server

The dynamics of spin-lattice relaxation (slr) of metal-organic Pt(II) compounds is studied. Often, such systems are characterized by pronounced zero-field splittings (zfs) of the lowest-lying triplets. Previous expressions for the Orbach slr process do not allow to treat such splitting patterns properly. We discuss the behavior of a modified Orbach expression for a model system and present results of a fit of the temperature dependence of the spin-lattice relaxation rate of Pt(2-thpy)$_2$ based on the modified expression.

CERN Document Server

We construct representation of the Separated Variables (SoV) for the quantum SL(2,R) Heisenberg closed spin chain and obtain the integral representation for the eigenfunctions of the model. We calculate explicitly the Sklyanin measure defining the scalar product in the SoV representation and demonstrate that the language of Feynman diagrams is extremely useful in establishing various properties of the model. The kernel of the unitary transformation to the SoV representation is described by the same "pyramid diagram" as appeared before in the SoV representation for the SL(2,C) spin magnet. We argue that this kernel is given by the product of the Baxter Q-operators projected onto a special reference state.

Energy Technology Data Exchange (ETDEWEB)

The RSS collaboration has measured the spin structure functions of the proton and the deuteron at Jefferson Lab using the Hall C HMS spectrometer, a polarized electron beam and a polarized solid target. The asymmetries A and A were measured in the region of the nucleon resonances (0.82 GeV < W < 1.98 GeV) at an average four momentum transfer of Q2 = 1.3 GeV2. The extracted spin structure functions and their kinematic dependence will make a significant contribution in the study of higher-twist effects and polarized duality tests. A description of the experiment and the latest findings of the analysis will be presented.

International Nuclear Information System (INIS)

Impurity effects on the photon-assisted spin-polarized transport through armchair carbon nanotubes connected with ferromagnetic leads are investigated theoretically. The impurity induces one resonant state whose position depends on the impurity strength, which can break the electron-hole symmetry. Whether the impurity suppresses or enhances the spin-coherent current depends on the nanotube length. When the microwave fields are applied on the nanotube, additional small side peaks caused by the photon-assisted tunneling are found. With increasing the impurity strength, one new current peak appears under the influence of both the microwave fields and the impurity.

Energy Technology Data Exchange (ETDEWEB)

Decay sequences based on the 1/2/sup +/(660) proton orbital have been identified in /sup 171/Ta and /sup 177/Re based on spin, parity, and large alignment. This decay sequence is observed higher in energy than predicted in cranking calculations based on modified oscillator potentials. Similarly known 1/2/sup -/(541) decay sequences in these and other neighbouring isotopes are observed lower in energy than predicted. A reduction in the strength of the spin-orbit potential for protons is suggested as a solution to these problem.

Energy Technology Data Exchange (ETDEWEB)

We present ab-initio calculations of the electronic structure of small Fe clusters (1-9 atoms) on Ni(001), Ni(111), Cu(001) and Cu(111) surfaces. Our focus is on the spin moments and their dependence on cluster size and shape. We derive a simple quantitative rule that relates the moment of each Fe atom linearly to its coordination number. Thus, for an arbitrary Fe cluster the spin moment of the cluster and of the individual Fe atoms can be readily found if the positions of the atoms are known. (orig.)

International Nuclear Information System (INIS)

We review recent progress on experimental studies of collective charge excitations in hole-doped spin ladder system Sr_1_4_-_xCa_xCu_2_4O_4_1, focusing on anomalous features of phase excitation. We also discuss possible candidates for related charge ordered state, together with a controversial issue of the hole density transferred from spin chain layers to spin ladder layers. (author)

KoreaScience (Korea)

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International Nuclear Information System (INIS)

... 900526-11-8 277 p. MATERIALS SCIENCE antiferromagnetic materials cerium

Energy Technology Data Exchange (ETDEWEB)

In the invar alloy (Fe{sub 0.65}Ni{sub 0.35}){sub 1-} {sub x} Mn {sub x} we measured the magnetic form factor s(Q) and the intermediate scattering function s(Q,t) for a sample close to the critical Mn concentration (x {sub c}=0.139), at which the sample turns to a re-entrant spin glass phase. The aim was to check whether the magnetic behaviour would approach the Q-independent relaxation behaviour of a classical spin glass when x=x {sub c}. The experiment showed a quite similar spin freezing as for a more ferromagnetic sample with x=0.113. The intermediate scattering function and the form factor were determined by paramagnetic NSE. The normalized scattering function S(Q,t)=s(Q,t)/s(Q)=exp[(-{gamma}t) {sup n}] was fitted by stretched exponential decay. As a function of temperature T<200 K the inverse time constant {gamma} showed the change of more than four orders of magnitude from frozen spin ...

Science.gov (United States)

... Results of the AXI5345-18 Motor, Jeti Spin 99 Controller and the APC 27 x 13 Propeller in use with a Linearized Fuel Cell Model Assuming Voc ...

Energy Technology Data Exchange (ETDEWEB)

There is considerable interest in the use of silicon devices as qubits for quantum computing. The existence of nuclear spin in a silicon isotope and the complex band structure of silicon are unfavourable for this application of silicon devices. (viewpoint)

Science.gov (United States)

You can find a discussion of time travel and Tipler's cylinder at this site: http://www.star-names.freeserve.co.uk/travel.htm ...

Energy Technology Data Exchange (ETDEWEB)

No abstract prepared.

International Nuclear Information System (INIS)

The exclusive electroproduction of ?0 mesons was studied with the HERMES spectrometer at the DESY laboratory by scattering 27.6 GeV positron and electron beams off a transversely polarized hydrogen target. Spin density matrix elements for this process were determined from the measured production- and decay-angle distributions of the produced ?0 mesons. These matrix elements embody information on helicity transfer and the validity of s-channel helicity conservation in the case of a transversely polarized target. From the spin density matrix elements, the leading-twist term in the single-spin asymmetry was calculated separately for longitudinally and transversely polarized ?0 mesons. Neglecting s-channel helicity changing matrix elements, results for the former can be compared to calculations based on generalized parton distributions, which are sensitive to the contribution of the total angular momentum of the quarks to the ...

Science.gov (United States)

High Cycle Fatigue Initiative Workshop -Active Vibration. Control/Engine. Health Monitoring Session December 10,. 1996. The presentation was titled "Active ...

Energy Technology Data Exchange (ETDEWEB)

The partial oxidation of 1,3-butadiene has been investigated over VMoO catalysts synthesized by sol-gel techniques. Surface areas were 9-14 m{sup 2}/g, and compositions were within the solid solution regime, i.e. below 15.0 mol % MoO{sub 3}/(MoO{sub 3} + V{sub 2}O{sub 5}). Laser Raman Spectroscopy and XRD data indicated that solid solutions were formed, and pre- and post-reaction XPS data indicated that catalyst surfaces contained some V{sup +4} and were further reduced in 1,3-butadiene oxidation. A reaction pathway for 1,3-butadiene partial oxidation to maleic anhydride was shown to involve intermediates such as 3,4-epoxy-1-butene, crotonaldehyde, furan, and 2-butene-1,4-dial. The addition of water to the reaction stream substantially increased catalyst activity and improved selectivity to crotonaldehyde and furan at specific reaction temperatures. At higher water addition concentrations, furan selectivity increased from 12% to over 25%. The catalytic effects of water addition were ...

International Nuclear Information System (INIS)

This paper reports on the electron current to a Langmuir probe in a moving high-pressure plasma. The plasma is an atmospheric-pressure propane flame, and the probe's speed relative to the plasma is varied from 10 to 30 ms"-"1. The current is linearly dependent on the speed and appears to be comprised of two components - one driven by diffusion and the other by convection. A model is devised which can be used to measure the electron density. By comparing the density computed from this model to that measured from the ion current, it has been possible to measure the electron mobility in the flame gases. The value obtained here is in good agreement with theoretical calculations found in the literature.

International Nuclear Information System (INIS)

We consider a D-brane probe in the unstable string background associated with flux branes. The twist in the spacetime metric reponsible for supersymmetry breaking is shown to manifest itself in the mixing of open Wilson lines with the phases of some adjoint matter fields, resulting in a nonlocal and nonsupersymmetric form of Yang-Mills theory as the probe dynamics. This provides a setup where one can study the fate of a large class of unstable closed string theories that includes as a limit type 0 theories and various orbifolds of type II and type 0 theories. We discuss the limit of C/Z_n orbifold in some detail and speculate on the couplings with closed string tachyons.

Science.gov (United States)

single star evolution. To understand the evolution of massive stars and their role in shaping the galaxy, understanding of the distribution of ...

International Nuclear Information System (INIS)

... obtain the film thickness for a given x-ray intensity ratio. 2.3 ANALYSING FOR

Science.gov (United States)

of the determinant of the parameter covariance matrix for each ... parameter covariance matrix, as obtained from the Markov chains. The basic set ...

Energy Technology Data Exchange (ETDEWEB)

With the improvements accomplished during the past 15 years in detection techniques and instrumentation and with the opening of space exploration, molecular spectroscopy has become a very efficient way to probe planetary atmospheres.

Science.gov (United States)

... A second hydrometeor sampler (MRI Model 1220 ... The cloud particle probe normally installed in ... to the northeast showed no significant movement. ...

Science.gov (United States)

... Accession Number : ADD336001. Title : Development of a FeCoNb Alloy to be used in Eddy Current Probes for Testing Ferromagnetic Tubes,. ...

Science.gov (United States)

Briefly, 48 MOS microparticle sensors (essentially the same as those flown on .... at the Naval Research Lab to interpret the polarization of the incoming radio .... Adapter Satellite, to be published in Journal of Spacecraft and Rockets, 1994. ...

International Nuclear Information System (INIS)

Based on proposed models for the tidal spin-up and magnetic braking of stars with a convective outer envelope, it is suggested that the rotation of secondaries in cataclysmic variables is not necessarily synchronized with the orbital revolution. This may provide an explanation for the observed large range in the mass transfer rate (at the same orbital period) of cataclysmic variables above the period gap. (author).

Energy Technology Data Exchange (ETDEWEB)

In calculating the strengths of depolarizing resonances it may be convenient to reformulate the equations of spin motion in a coordinate system based on the actual trajectory of the particle, as introduced by Kondratenko, rather than the conventional one based on a reference orbit. It is shown that resonance strengths calculated by the conventional and the revised formalisms are identical. Resonances induced by radiofrequency dipoles or solenoids are also treated; with rf dipoles it is essential to consider not only the direct effect of the dipole but also the contribution from oscillations induced by it.

International Nuclear Information System (INIS)

In YbPd_2Si_2, the valence of Yb is very close to 3+. Ge substitution of Si induces a negative pressure effect and the valence of Yb decreases. For the low Ge concentrations studied, the spin fluctuation temperature T_s_f increases and #chi#4f, the Yb derived 4f susceptibility, obeys the scaling law #chi#4f(T)=F(T/T_s_f). (orig.).

UK PubMed Central (United Kingdom)

The alternative low-spin states of Fe³⁺ and Fe²⁺ cytochrome c induced by SDS or AOT/hexane reverse micelles exhibited the heme group in a less...Full Text Available

Energy Technology Data Exchange (ETDEWEB)

Measurements of the two-body recombination of spin-polarized atomic hydrogen in a magnetic field of 40 kG have been extended to temperatures above 0.5/sup 0/K. The rate constant for the formation of parahydrogen shows an unexpected increase with temperature, which is explained by inverse predissociation into the v = 14,J = 4 level of H/sub 2/. Data indicate the level is bound by 0.7 +- 0.1/sup 0/K.

International Nuclear Information System (INIS)

The phenomenological description of the giant magnetoresistance effect as well as discussion of the requirements which must be fulfilled in giant magnetoresistance thin film structures are given in the first part of our review. In the second part the magnetization reversal and giant magnetoresistance effect of antiferromagnetically coupled multilayers, spin Valve and pseudo-spin valve thin film structures are explained. For these structures we also discuss the influence of the structure defects such as surface roughness and pinholes on the giant magnetoresistance effect. (author)

Energy Technology Data Exchange (ETDEWEB)

The existence of propagating spin waves above T/sub c/ in Ni and Fe has been widely accepted since this picture was first advocated in 1973. In this brief review of our current neutron scattering experiments on Fe and Ni we will present convincing evidence showing that this picture is incorrect. In addition, we will demonstrate that over wide ranges of ..omega.., q and temperature, both Fe and Ni follow a simple paramagnetic scattering function of the spin diffusion type. 19 references.

Energy Technology Data Exchange (ETDEWEB)

Some applications of magnetic resonance in coal liquefaction research described briefly are: (1) investigation of the nature of carbon deposits on used coal-liquefaction catalysts, (2) determination of the fate of hydrogen during coal liquefaction, and (3) observation of transient free radicals during coal pyrolysis. The first two applications make use of cross-polarization /sup 13/C magnetic resonance combined with magic angle spinning, and the third application is an electron spin resonance study. (BLM)

International Nuclear Information System (INIS)

Low spin states (Jspin states is found in "1"8"7Ir to which this theory is applied. (Auth.).

International Nuclear Information System (INIS)

We study the spin dependence of accretion onto rotating Kerr black holes using analytic techniques. In its linear regime, angular momentum transport in MHD turbulent accretion flow involves the generation of radial magnetic field connecting plasma in a differentially rotating flow. We take a first principles approach, highlighting the constraint that limits the generation and amplification of radial magnetic fields, stemming from the transfer of energy from mechanical to magnetic form. Because the energy transferred in magnetic form is ultimately constrained by gravitational potential energy or Killing energy, the spin dependence of the latter allows us to derive spin-dependent constraints on the success of the accreting plasma to expel its angular momentum. We find an inverse relationship between this ability and black hole spin. If this radial magnetic field generation forms the basis for angular ...

CERN Document Server

We derive spin-orbit coupling effects on the gravitational field and equations of motion of compact binaries in the 2.5 post-Newtonian approximation to general relativity, one PN order beyond where spin effects first appear. Our method is based on that of Blanchet, Faye, and Ponsot, who use a post-Newtonian metric valid for general (continuous) fluids and represent pointlike compact objects with a delta-function stress-energy tensor, regularizing divergent terms by taking the Hadamard finite part. To obtain post-Newtonian spin effects, we use a different delta-function stress-energy tensor introduced by Bailey and Israel. In a future paper we will use the 2.5PN equations of motion for spinning bodies to derive the gravitational-wave luminosity and phase evolution of binary inspirals, which will be useful in constructing matched filters for signal analysis. The gravitational field derived here may help ...

International Nuclear Information System (INIS)

The use of europium as a local structural probe allows the various phases appearing in the NaCaPO_4-Na_3Eu(PO_4)_2 and NaSrPO_4-Na_3Eu(PO_4)_2 systems to be detected. The broadening of the europium emission lines in going from the calcium to the strontium phases illustrates the ease of displacement of the PO_4 groups. (Auth.).

Energy Technology Data Exchange (ETDEWEB)

Surface deposition probe techniques have been shown to be an effective means of determining the characteristics of the plasma edge region of magnetic confinement devices. Experimental results on ISX-B and EBT-S have led to a consistent picture of the edge plasma and the dominant impurity introduction mechanisms. This picture is supported by numerous other measurements and emphasizes the importance of concentrating several techniques on the complex problems of plasma fusion.

Science.gov (United States)

Procedures are described for the use of synthetic oligonucleotides for Southern blot experiments and gene bank screening, and the effect of various mismatches on the efficiency of hybridization is demonstrated. The following topics are discussed: sensitivity vs. specificity, hybridization of a 12-mer to the lambda endolysin gene; hybridization of oligonucleotide probes to the E. coli lac operator; hybridization of synthetic probes to the CYC1 gene of yeast; and cloning eucaryotic genes. (HLW)

Energy Technology Data Exchange (ETDEWEB)

Nondestructive inspection of carbon fibre-reinforced plastics (CRFP) using eddy current methods is based not only on the conductivity of the fibres. High frequencies (up to 10 MHz) give access to capacitive effects reflecting properties of the matrix. The paper presents a method using rotating eddy current probes to measure the anisotropic electrical properties. Potential applications of this method are the structural identification of laminates and the estimating of its degradation. (orig.)

International Nuclear Information System (INIS)

In in-service inspection of steam-generator tubes, the need for reproducibility of the measurement results and for comparison of these results over two successive inspections has led EDF to specify the main characteristics of the eddy-current probes and to design equipment to measure them. This equipment is presented here and the electrical and magnetic results are correlated with those obtained by testing tubes with reference defects.

British Library Electronic Table of Contents (United Kingdom)

An eddy current probe of the level of molten metal is considered for a sectional machine of continuous casting of steel. The advantages of electromagnetic probes of the level over radiometric ones lie in their insensitivity to the layer of dross and high speed. The results and directions of further studies are given.

Energy Technology Data Exchange (ETDEWEB)

Geometrically anisotropic eddy current probes are a type of separate function probes especially fit to the detection of defects showing a preferential direction. This kind of flaw induces a coupling between the transmitter and the receiver by guiding eddy currents from the one to the other. On the other hand, this coupling will be almost non-existent in the presence of defects or spurious effects not displaying this geometrical particularity. Basic studies on an elementary two-coil set-up allow the acknowledgment of the intrinsic qualities of such probes: good signal-to-noise ratio, influence field practically constant on the whole defect length, ability to detect bridged defects, insensitivity to lift off. These results can be improved by achieving multicoils probes adapted to different kinds of problems. An application to continuous casting slabs testing yields very interesting results in the ...

Energy Technology Data Exchange (ETDEWEB)

Understanding the structure of the nucleon is a fundamental question in subatomic physics, and it has been under intensive investigation for the last several years. Modern research focuses in particular on the spin structure of the nucleon. Experimental and theoretical investigations worldwide over the last few decades have established that, contrary to nave quark model expectations, quarks carry only about 30% of the totd spin of the proton. The origin of the remaining spin is the key question in current hadronic physics and also the major driving forces for the current and future experiments, such as RHIC and CEBAF in US, JPARC in Japan, COMPASS at CERN in Europe, FAIR at GSI in Germany. Among these studies, the transverse-spin physics develops actively and rapidly in the last few years. Recent studies reveal that transverse-spin physics is closely related to many fundamental ...

International Nuclear Information System (INIS)

The future use of single-molecule magnets in applications will require the ability to control and manipulate the spin state and magnetization of the magnets by external means. There are different approaches to this control, one being the modification of the magnets by adsorption of small ligand molecules. In this paper we use iron phthalocyanine supported by an Au(111) surface as a model compound and demonstrate, using x-ray photoelectron spectroscopy and density functional theory, that the spin state of the molecule can be tuned to different values (S #approx# 0, 1/2, 1) by adsorption of ammonia, pyridine, carbon monoxide or nitric oxide on the iron ion. The interaction also leads to electronic decoupling of the iron phthalocyanine from the Au(111) support. (fast track communication)

CERN Document Server

We have monitored a Type II outburst of the Be/X-ray binary MXB 0656-072 in a series of pointed RXTE observations during October through December 2003. The source spectrum shows a cyclotron resonance scattering feature at 32.8 +/- 0.5 keV, corresponding to a magnetic field strength of (3.67 +/- 0.06) x 10^12 G and is stable through the outburst and over the pulsar spin phase. The pulsar, with an average pulse period of 160.4 +/- 0.4 s, shows a spin-up of 0.45 s over the duration of the outburst. From optical data, the source distance is estimated to be 3.9 +/- 0.1 kpc and this is used to estimate the X-ray luminosity and a theoretical prediction of the pulsar spin-up during the outburst.

DEFF Research Database (Denmark)

We suggest and study designed defects in an otherwise periodic potential modulation of a two-dimensional electron gas as an alternative approach to electron spin based quantum information processing in the solid-state using conventional gate-defined quantum dots. We calculate the band structure and density of states for a periodic potential modulation, referred to as an antidot lattice, and find that localized states appear, when designed defects are introduced in the lattice. Such defect states may form the building blocks for quantum computing in a large antidot lattice, allowing for coherent electron transport between distant defect states in the lattice, and for a tunnel coupling of neighboring defect states with corresponding electrostatically controllable exchange coupling between different electron spins.

International Nuclear Information System (INIS)

We have used polarised neutrons to measure the integrated magnetic cross-section of a dilute alloy of Ce in Y a Kondo system, T_K#approx#40 K. Previous polarised neutron measurements of the field-induced magnetic form factor found no anomalies that could be attributed to the formation of a spin compensation cloud around the Ce ion. The present measurements, focused on the diffuse low-Q range, represent information over a very wide length scale in real space. Again, they show no changes in the Q-dependence of the form-factor at low temperatures that could be attributed to the formation of a spin compensation cloud. An alternative interpretation of the phenomenon based on the dynamical magnetic susceptibility of Y-Ce is proposed.

British Library Electronic Table of Contents (United Kingdom)

Herein, we demonstrate the structure of the PS colloidal crystals which were fabricated on the hydrophilic/hydrophobic Si wafers by a spin-coating technique. Monodisperse PS colloids are spin-coated onto self-assembled monolayers of 3-(aminopropyl)triethoxysilane and propyltrimethoxysilane coated Si wafers. PS spheres organized as ordered close-packed face-centered cubic structure with (111) planes on the hydrophilic surface while they gathered without the crystal structure on the hydrophobic surface. This paper also reports a simple and rapid method to fabricate the close-packed structure of hollow TiO2 spheres. The colloidal crystal of TiO2 hollow spheres was prepared using the PS sphere template on the hydrophobic surface. The mechanism for the growing multilayers of self-assembled PS p...

CERN Document Server

We construct the Baxter Q-operator and the representation of the Separated Variables (SoV) for the homogeneous open SL(2,R) spin chain. Applying the diagrammatical approach, we calculate Sklyanin's integration measure in the separated variables and obtain the solution to the spectral problem for the model in terms of the eigenvalues of the Q-operator. We show that the transition kernel to the SoV representation is factorized into the product of certain operators each depending on a single separated variable. As a consequence, it has a universal pyramid-like form that has been already observed for various quantum integrable models such as periodic Toda chain, closed SL(2,R) and SL(2,C) spin chains.

International Nuclear Information System (INIS)

A new eddy current array probe has been implemented as a straightforward and promising technique for detection of outer diameter (OD) surface-breaking cracks on the extrados of feeder bends. The design is based on previous work performed at AECL, which had demonstrated that eddy current probes with laterally displaced transmit-receive coils can overcome some of the limitations of inspecting ferritic steel components for surface-breaking cracks. The Feeder Integrity Joint Program-CANDU Owners Group Inc. (FIJP-COG) Non-Destructive Evaluation (NDE) Team members commissioned AECL to work in collaboration with the probe manufacturer ZETEC, to develop a field usable eddy current array probe. The objective was to acquire a technique with the following capabilities: fast scanning non-contact inspection technique for surface breaking discontinuities; full inspection of the bend extrados OD surface in a single ...

British Library Electronic Table of Contents (United Kingdom)

This work reports the development of an automatic methodology based on the use of 1-anilinonaphthalene-8-sulfonate (ANS) as an interfacial fluorescent probe for detecting the hydrophobic environment shift around the probe, caused by the hydrolytic action of PLA2 on the liposomes. The implementation of this reaction in a sequential injection analysis (SIA) system along with the use of the mixing chambers permitted the evaluation of PLA2 activity and assessment of the inhibitory effect of the non-steroidal anti-inflammatory drugs (NSAIDs) on PLA2 activity. Several studies were performed with the aim of establishing the appropriate flow system configuration: the liposome substrate; PLA2 and ANS optimum concentrations and incubation times before and after the enzyme addition. Based on these st...

International Nuclear Information System (INIS)

We analyze the potential of the e"+e"- linear colliders, operating in the e#gamma# and #gamma##gamma# modes, to probe anomalous quartic vector-boson interactions through the multiple production of W's and Z's. We examine all SU(2)_L(circle times)U(1)_Y chiral operators of order p"4 that lead to new four-gauge-boson interactions but do not alter trilinear vertices. We show that the e#gamma# and #gamma##gamma# modes are able not only to establish the existence of a strongly interacting symmetry breaking sector but also to probe for anomalous quartic couplings of the order of 10"-"2 at 90% C.L. Moreover, the information gathered in the e#gamma# mode can be used to reduce the ambiguities of the e"+e"- mode.

Energy Technology Data Exchange (ETDEWEB)

This research deals with in the study of the use of innovating magnetic sensors in eddy current non destructive inspection. The author reports an analysis survey of magnetic sensor performances. This survey enables the selection of magnetic sensor technologies used in non destructive inspection. He presents the state-of-the-art of eddy current probes exploiting the qualities of innovating magnetic sensors, and describes the methods enabling the use of these magnetic sensors in non destructive testing. Two main applications of innovating magnetic sensors are identified: the detection of very small defects by means of magneto-resistive sensors, and the detection of deep defects by means of giant magneto-impedances. Based on the use of modelling, optimization, signal processing tools, probes are manufactured for these both applications.

Energy Technology Data Exchange (ETDEWEB)

The ISI (In-Service Inspection) system has been developed so as to maintain the structural integrity of heat transfer tubes in the primary pressurized water cooler in the HTTR (High Temperature Engineering Test Reactor). This system consists of eddy current probes, ultra-sonic probes, insertion and extraction units, positioning unit and so on. Verification and performance tests of the developed ISI system were carried out using mock-up heat transfer tubes in the primary pressurized water cooler. The constitution of the system, R and D results of the inspection probes, and verification and performance test results of the ISI system for heat transfer tubes are described in this paper. (author)

Energy Technology Data Exchange (ETDEWEB)

A spectroscopic study is performed for high spin states of {sup 55}Fe, {sup 55}Co and {sup 57}Ni. To populate the investigated residues with a relevant cross section, the fusion evaporation reactions of {sup 30}Si({sup 28}Si, 2pn){sup 55}Fe, {sup 30}Si({sup 28}Si, 2pn){sup 55}Co and {sup 4}He({sup 54}Fe, n){sup 57}Ni were chosen. To identify the new {gamma} transitions and to build the energy level schemes, {gamma}-{gamma} coincidence techniques together with excitation functions were employed. Angular distributions and {gamma}-{gamma} angular correlations allowed us to assign the spin values of the nuclear states. The previous level scheme of {sup 55}Fe is extended into the region between 6.5-11 MeV of excitation energy, up to spin 27/2, while the yrast decay pathos of {sup 57}Ni and {sup 55}Co are reported here for the first time. Experimental data are fairly well reproduced by Glaudemans' shell model ...

CERN Document Server

We report $^{7}$Li pulsed NMR measurements in polycrystalline and single crystal samples of the quasi one-dimensional S=1 antiferromagnet LiVGe$_2$O$_6$, whose AF transition temperature is $T_{\\text{N}}\\simeq 24.5$ K. The field ($B_0$) and temperature ($T$) ranges covered were 9-44.5 T and 1.7-300 K respectively. The measurements included NMR spectra, the spin-lattice relaxation rate ($T_1^{-1}$), and the spin-phase relaxation rate ($T_2^{-1}$), often as a function of the orientation of the field relative to the crystal axes. The spectra indicate an AF magnetic structure consistent with that obtained from neutron diffraction measurements, but with the moments aligned parallel to the c-axis. The spectra also provide the $T$-dependence of the AF order parameter and show that the transition is either second order or weakly first order. Both the spectra and the $T_1^{-1}$ data show that $B_0$ has at most a small effect on the alignment of the AF ...

Energy Technology Data Exchange (ETDEWEB)

We extend Winger's work on the wave equations for integer-spin particles to the spinorial case. A recent suggestion that the neutrino might be a fermionic tachyon is examined. We point out that a four-component Dirac equation cannot describe fermionic tachyon. (orig.).

UK PubMed Central (United Kingdom)

A technique of low-field pulsed proton nuclear magnetic resonance (NMR) spin relaxation is described for assessment of age-related structural changes (dentin and pulp) of human teeth in...Full Text Available

Science.gov (United States)

Black Hole Drawing Credit: A. Hobart, CXC Explanation: In the center of a swirling whirlpool of hot gas is likely a beast that has never been seen directly: a black hole....

Science.gov (United States)

Black Hole Drawing Credit: A. Hobart, CXC Explanation: In the center of a swirling whirlpool of hot gas is likely a beast that has never been seen directly: a black hole....

UK PubMed Central (United Kingdom)

BackgroundTranslating research to make it more understandable and effective (research translation) has been declared a priority in environmental health but does not always include...Full Text Available

Energy Technology Data Exchange (ETDEWEB)

We duscuss a resonant microwave trap for neutral atoms. Because of the long spontaneous radiation time this trap is remarkably different from the optical trap. It also has advantages over static magnetic traps that trap the excited spin state of the lowest electronic level, in that atoms predominantly in the spin ground state can be trapped. We analyze the relaxation-ejection lifetime of atoms in such a trap using the formalism of dressed atomic states. Results are appliedi to atomic hydrogen and the possibility of Bose-Einstein condensation is considered.

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Application to carbon fiber started in this Year. In this paper, a spinning and calcination process are explained. Fiber was obtained by wet spinning of the PAN solution. Ten solvents were tested and the results proved that dimethyl sulfoxide (DMSO) was the best solvent. Glycerine was used as a coagulating bath. The thin fiber (10 to 50 denier) was produced under the conditions of about 20wt% concentration at about 110degC. Heat-treat temperature was about 270 to 275degC. The viscosity-tacticity relationship and T{sub sol} vs. inverse tacticity were shown in the paper. (S.Y.)

Energy Technology Data Exchange (ETDEWEB)

I review recent developments in quark-hadron duality in inclusive electron-nucleon scattering. Matrix elements of twist-4 operators extracted from moments of the spin-dependent g1 structure function suggest that duality violating higher twists are small above Q2 {approx} 1 GeV2. The x dependence of local duality is analyzed within a quark model framework, and mechanisms are identified for spin-flavor symmetry breaking which underpin the behavior of structure functions at large x.

CERN Document Server

The possibility of the existence of stable tetrahedral deformations at spin zero is investigated using the Skyrme-HFBCS approach and the generator coordinate method (GCM). The study is limited to nuclei in which the tetrahedral mode has been predicted to be favored on the basis of non self-consistent models. Our results indicate that a clear identification of tetrahedral deformations is unlikely as they are strongly mixed with the axial octupole mode. However, the excitation energies related to the tetrahedral mode are systematically lower than those of the axial octupole mode in all the nuclei included in this study.

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Extended conformal algebras with supersymmetry (super-W/sub n/ algebra) is constructed and the algebras are shown to exist for special values of the central charge c. The super-W/sub n/ algebra containing currents of spin (5/2, 3) has a unitary representation (c=10/7) and a non-unitary one (c=-5/2), and the super-W/sub n/ algebra containing currents of spins (2, 5/2) has a non-unitary representation (c=-6/5).

Energy Technology Data Exchange (ETDEWEB)

Eight cross spiders (Araneus diadematus) were exposed overnight (16 h) during web-building activity to pulsed 9.6-GHz microwaves at average power densities of 10, 1, and 0.1 mW/sq. cm. (estimated SARs 40, 4, and 0.4 mW/g). Under these conditions, 9.6-GHz pulsed microwaves did not affect the web-spinning ability of the cross spider.

Science.gov (United States)

The interaction between N-donor adsorbates such as ammonia and pyridine with Cu(II)-exchanged montmorillonite, beidellite, flourohectorite into smectite clays has been studied by electron spin resonance. Cu(II) cations exchanged into smectites coordinate five ammonia or pyridine molecules in beidellite, four ammonia of pyridine molecules in hydroxyhectorite. Thus, the Cu(II) cations bound to the interior surfaces of these smectite clays constitute strong Lewis acid sites. 26 refs., 7 figs., 1 tab.

International Nuclear Information System (INIS)

A CANDU nuclear reactor was shut down for over one year because steam generator (SG) tubes had failed with outer diameter stress-corrosion cracking (ODSCC) in the U-bend section. Novel, single-pass eddy current transmit-receive probes, denoted as C3, were successful in detecting all significant cracks so that the cracked tubes could be plugged and the unit restarted. Significant numbers of tubes with SCC were removed from a SG in order to validate the results of the new probe. Results from metallurgical examinations were used to obtain probability-of-detection (POD) and sizing accuracy plots to quantify the performance of this new inspection technique. Though effective, the above approach of relying on tubes removed from a reactor is expensive, in terms of both economic and radiation-exposure costs. This led to a search for more affordable methods to validate inspection techniques and procedures. Methods are presented for calculating POD curves ...

UK PubMed Central (United Kingdom)

AbstractThe structural integrity of striated muscle is determined by extra-sarcomere cytoskeleton that includes structures that connect the Z-disks and M-bands of a sarcomere to sarcomeres...Full Text Available

UK PubMed Central (United Kingdom)

The ability to directly compare gastric ulcerated and healthy tissue would aid in the understanding of the physiological differences between these tissue types. Presently, these comparisons...Full Text Available

UK PubMed Central (United Kingdom)

The relative sensitivities of different protocols for detecting cytomegalovirus nucleic acid sequences in histological specimens, using a biotinylated cDNA probe, were assessed. Several commonly used...Full Text Available

UK PubMed Central (United Kingdom)

The T-loop motif is an important recurrent RNA structural building block consisting of a U-turn sub-motif and a UA trans Watson–Crick/Hoogsteen base pair. In the presence of...Full Text Available

UK PubMed Central (United Kingdom)

We describe the characteristics of the rapidly rotating molecular disk in the nucleus of the mildly active galaxy NGC4258. The morphology and kinematics of the disk are delineated by the point-like...Full Text Available

UK PubMed Central (United Kingdom)

Failures in cortical control of fronto-striatal neural circuits may underpin impulsive and compulsive acts. In this narrative review, we explore these behaviors from the perspective of neural processes...Full Text Available

UK PubMed Central (United Kingdom)

The imaging analytical capabilities of laser scanning cytometer (LSC) have been used to assess morphological features considered to be typical of the senescent phenotype. The characteristic “flattening”...Full Text Available

Energy Technology Data Exchange (ETDEWEB)

Eddy current inspection methods are widely used for the nondestructive evaluation (NDE) of tubular products. Specifically, the sensors and instrumentation are designed to detect and characterize changes in a material's electrical and magnetic properties produced by the presence of discontinuities. A recent major enhancement in eddy current inspection technology has been the development of computer interfacing for data collection, analysis, and display. This breakthrough has led to multiple-frequency testing, eddy current imaging, and automated data interpretation systems that significantly enhance both capabilities and reliability of the eddy current inspection. In addition to the clear advantages in data processing, computer interfacing also permits the design and creation of unique sensors that further enhance eddy current inspection capabilities. Perhaps the most promising area of computer interactive probe design is multiple element sensors. ...

Energy Technology Data Exchange (ETDEWEB)

This report describes the results of EPRI Program S404-28, titled Experimental Modeling of Eddy Current Response'', conducted by the Westinghouse Science and Technology Center (STC). The Westinghouse STC demonstrates that its mercury modeling technique provides an unique bridge between steam generator eddy current field inspection conditions and predictions obtained using recently developed analytical models. The mercury modeling technique was used systematically to explore factors which contribute to primary water stress corrosion cracking (PWSCC) sizing inaccuracy, including probe design, coil excitation frequency, crack length, and crack morphology. Two new proposed techniques for inverting crack lengths from eddy current data are compared with the technique commonly used in field data analysis for PWSCC. The performance of uniform field eddy current probes is compared with the performance of pancake coil ...

UK PubMed Central (United Kingdom)

Despite prolonged scientific efforts to unravel the hydration structures of ions in water, many open questions remain, in particular concerning the existences and structures of ion clusters in 1∶1...Full Text Available

International Nuclear Information System (INIS)

The inspection of PFR evaporator tubing, superheater and reheater tubing, and tube plate examinations, are described. Ferritic steel U tubes in the evaporator have been examined by an eddy current system operating at 400 kHz using flexible rotating probes. Surface defects as shallow as 0.1 mm can be detected and sized in the range 0.1 to 0.5 mm deep. An ultrasonic method is under development for wall thickness. Special test coil probes have been developed for examination of the type 316 stainless steel superheater and reheater tubing. Crack-life defects in the bore are detectable at approximately 10% wall thickness and 20% on the outside diameter. Tube plate examinations from the tube holes, have been conducted using eddy current probes which identify surface breaking cracks in the holes. For detecting curtain cracks between tube plate holes, ultrasonic compression wave probes have been used. (U.K.).

Environmental Research Database

ObjectivesThe overall aim of this work is to use an in-situ FTIR probe to investigate selected heterogeneous catalysts in industrially relevant organic reactions. This approach will be broadly applicable to the UK fine chemical manufacturing base.~%~~%~The project has the following specific objectives:~%~~%~- To demonstrate and develop the use of an in-situ FTIR probe in a batch reactor at elevated temperatures (eg greater than 100 deg C) to monitor reactant usage and product formation.~%~~%~- To validat [continued...]DescriptionThis proposal concerns the in-situ study of catalytic processes and reaction kinetics. The catalysts concerned are microporous materials, such as, zeolites, containing pores and cavities of molecular dimensions. These catalysts constitute crystal reactors on a nanometer scale that are selective on a size and shape basis for organic molecules used in this ...

UK PubMed Central (United Kingdom)

Optical coherence microscopy (OCM) is a promising technique or high resolution cellular imaging in human tissues. An OCM system for high-speed en face cellular resolution imaging...Full Text Available

UK PubMed Central (United Kingdom)

The binding of amphiphilic molecules to lipid bilayers is followed by ¹⁹F NMR using chemical shift and line shape differences between the solution and membrane-tethered states of...Full Text Available

International Nuclear Information System (INIS)

Detection of fatigue damage cracks in aircraft skin structures is an ongoing NDT challenge. Cracks growing rate is difficult to predict, and for this reason, it is important to detect them as soon as possible to avoid a catastrophic break. Eddy current methods are known and well-accepted techniques which are relatively simple to carry out. However, with conventional inspection of airframe structures using standard driver-pickup eddy current probes, it is difficult to detect small fatigue cracks initiated in the second layer of the skin and in the shadow region at fastener holes. Such difficulty is related to fasteners length and their spacing which reduces test sensitivity. This report explains the development of improved eddy current probe/technique to detect and visualize fatigue cracks in fasteners. In this study, an eddy current array probe was evaluated and new coil design was suggested. Several tests were conducted on ...

Energy Technology Data Exchange (ETDEWEB)

Although ultrasonic testing inspection technology and tools have improved significantly, there is still a need for more reliable detection, monitoring, and accurate sizing of crack-like and planar defects, complex corrosion damage, and detection of secondary features within deformed pipe. Ultrasonic two dimensional (2D) matrix phased array technology offers some unique advantages that make the technology promising for improving detection and sizing of pipeline flaws resulting from welding or from in-service damage. Ultrasonic modeling and simulation has been conducted to evaluate the detection and sizing capabilities of 2D matrix arrays for various pipeline inspection concepts. Simulations have been performed using both flexible and rigid array probes. Inspection concepts using rigid probes were evaluated for inspections from both the outside and inside pipe surfaces, while flexible probes were evaluated primarily for ...

UK PubMed Central (United Kingdom)

Various physico-chemical tissue optical clearing (TOC) methods have been suggested to maximize photon density in tissue. In order to enhance photon density, a compression-controlled low-level...Full Text Available

UK PubMed Central (United Kingdom)

DNA barcodes linked to genetic features greatly facilitate screening these features in pooled formats using microarray hybridization, and new tools are needed to design large sets of barcodes to allow...Full Text Available

UK PubMed Central (United Kingdom)

Three nucleic acid probes, two for autotrophic ammonia-oxidizing bacteria of the beta subdivision of the class Proteobacteria and one for alpha subdivision nitrite-oxidizing bacteria, were developed...Full Text Available

International Nuclear Information System (INIS)

Heat transfer tubes of a primary pressurized water cooled (PPWC) in the high temperature engineering test reactor (HTTR) form the reactor pressure boundary of the primary coolant, therefore are important from the viewpoint of safety. To establish inspection techniques for the heat transfer tubes of the PPWC, an automatic inspection system was developed. The system employs a bobbin coil probe, a rotating probe for eddy current testing (ECT) and a rotating probe for ultrasonic testing (UT). Nondestructive test of a half of the heat transfer tubes of the PPWC was carried out by the automatic inspection system during reactor shutdown period of the HTTR (about 55% in the maximum reactor power in this paper). The nondestructive test results showed that the maximum signal-to-noise ratio was 1.8 in ECT. Pattern and phase of Lissajous wave, which were obtained for the heat transfer tube of the PPWC, were different from those ...

Science.gov (United States)

Probing Neutron Star Evolution with Gamma Rays Online Source: Click to View PDF File [PDF Size: 217 KB] Author: Wijers, Ralph A. M. J. ...

UK PubMed Central (United Kingdom)

Water-maze testing has been used to assess prenatal cocaine (PCOC)- induced deficits in behavioral studies of spatial navigation and memory abilities. Effects of PCOC in acquisition or in probe...Full Text Available

Energy Technology Data Exchange (ETDEWEB)

The use of europium as a local structural probe allows the various phases appearing in the NaCaPO/sub 4/-Na/sub 3/Eu(PO/sub 4/)/sub 2/ and NaSrPO/sub 4/-Na/sub 3/Eu(PO/sub 4/)/sub 2/ systems to be detected. The broadening of the europium emission lines in going from the calcium to the strontium phases illustrates the ease of displacement of the PO/sub 4/ groups.

Energy Technology Data Exchange (ETDEWEB)

Results are given for deep-level petroleum and gas drilling probes in various coastal zones of Southern Sakhalin covering the Poronai depression and the Aniv Bay trough. The exploratory probes indicate that the Middle Miocence deposits of the Boundary trough contain commercial-size deposits of petroleum, that commercial-size gas deposits are in the upper Myocene deposits of the Aliv Bay trough, and that the upper Cretaceous and Cenozoic deposits of the eastern section of Southern Sakhalin lack folded deformations. 7 references, 2 figures.

International Nuclear Information System (INIS)

Secondary-electron emission (SEE) spectra have been obtained with the Scanning Probe Energy Loss Spectrometer at a tip-sample distance of only 50 nm. Such short working distances are required for the best theoretical spatial resolution (<10 nm). The SEE spectra of graphite, obtained as a function of tip bias voltage, are shown to correspond to unoccupied states in the electronic band structure. The SEE spectra of thin gold films demonstrate the capability of identifying (carbonaceous) surface contamination with this technique.

International Nuclear Information System (INIS)

This paper describes detection of electro-discharged machine (EDM) defects in magnetic steam generator (SG) tubes of Monju fast breeder reactor (FBR). The EDM defects are located under support plate (SP), on the outer tube surface and they are detected by a remote field eddy current probe. Using the experimental measurements and a multi frequency algorithm, the defect signal can be extracted from the SP signal. The parameters of the multi-frequency algorithm were calculated by comparing SP measurements with two-dimensional finite element simulations (FEM). (author)

International Nuclear Information System (INIS)

In one of the first uses of high Tc superconductors in an end-use product, Lake Shore Cryotronics and a Swiss lab have developed a liquid nitrogen level sensor using a high Tc thin film. The probe is manufactured using a seamless stainless steel tube with an yttrium-based zirconium oxide flame-sprayed on the tube. A plasma-sprayed superconductor compound is deposited on top of that. The probe is coated with a sealant that protects the superconducting film from the atmosphere. This manufacturing method has yielded an extremely durable product. Unaffected by ice formation and related mechanical problems, the superconducting level sensor can be kept in the dewar for long periods of time.

CERN Document Server

LHC$b$ is one the four major experiments at the Large Hadron Collider (LHC) at CERN. It is custom built to look for CP violation and New Physics in rare decays of heavy flavor hadrons, like the B and D systems. Rare decays that occur via loop diagrams provide a way to probe New Physics at energy scales much higher than can be probed by direct production in experiment. In this article, the LHC$b$ prospects for such measurement with exclusive decays of the type $B \\to X_s\\gamma$ and $B\\to X_sl^+l^-$ are presented.

International Nuclear Information System (INIS)

Eddy current testing (ECT) method is widely used as the non-destructive evaluation (NDE) of the various kinds of material degradation occurring in nuclear power plants (NPPs) components including steam generator (SG) tubes. Detection of any defects or flaws in the steam generator tubes in the early stage is very important in maintenance of NPP for its primary role as the pressure boundary with thin wall thickness. Although the ECT technique provides lots of information for a SG management, it has a generic problem in its reliability due to a low ability in detect of small defects and some difficulty in a signal analysis. For the improvement of these shortcomings in conventional ECT, profile-MRPC (motorized rotating pancake coil) ECT technology was developed in KAERI. The key of this new technology is the development of new eddy current probes, designated as a diagnostic probe (D-probe). The D-probe is ...

Energy Technology Data Exchange (ETDEWEB)

The WEGA stellarator is used to confine low temperature, overdense (densities exceeding the cut-off density of the heating wave) plasmas by magnetic fields in the range of B=50-500 mT. Microwave heating systems are used to ignite gas discharges using hydrogen, helium, neon or argon as working gases. The produced plasmas have been analyzed using Langmuir and emissive probes, a single-channel interferometer and ultra-high resolution Doppler spectroscopy. For a typical argon discharge in the low field operation, B=56 mT, the maximum electron density is n{sub e}{proportional_to}10{sup 18} m{sup -3} with temperatures in the range of T=4-12 eV. The plasma parameters are determined by using Langmuir probes and are cross-checked with interferometry. It is demonstrated within this work that the joint use of emissive probes and ultra-high resolution Doppler spectroscopy allows a precise measurement of the radial electric field. The ...

International Nuclear Information System (INIS)

This review describes the basic theory and some recently developed techniques for the study of quadrupole nuclei with half integer spins in powder materials. The latter is connected to the introduction of the double rotation (DOR) by A. Samoson et al. (1) and to the introduction of the multiple quantum magic-angle spinning (MQ MAS) technique by L. Frydman et. al. (2). For integer spins, especially the solid-state deuterium magnetic resonance, we refer to the review of G.L. Hoatson and R.L. Vold: ''"2H-NMR Spectroscopy of Solids and Liquid Crystals'' (3). For single crystals we refer to O. Kanert and M. Mehring: ''Static quadrupole effects in disordered cubic solids''(4) and we would like also to mention the ''classic'' review of M.H. Cohen and F. Reif: ''Quadrupole effects in NMR studies of solids'' (5). Some more recent reviews in the field under study are D. Freude and J. Haase ''Quadrupole effects in solid-state NMR'' ...

Energy Technology Data Exchange (ETDEWEB)

Corrosion probes are being developed and combined with an existing measurement technology to provide a tool for assessing the extent of corrosion of metallic materials on the fireside in coal-fired boilers. The successful development of this technology will provide power plant operators the ability to (1) accurately monitor metal loss in critical regions of the boiler, such as waterwalls, superheaters, and reheaters; and (2) use corrosion rates as process variables. In the former, corrosion data could be used to schedule maintenance periods and in the later, processes can be altered to decrease corrosion rates. The research approach involves laboratory research in simulated environments that will lead to field tests of corrosion probes in coal-fired boilers. Laboratory research has already shown that electrochemically-measured corrosion rates for ash-covered metals are similar to actual mass loss corrosion rates. Electrochemical tests conducted ...

Science.gov (United States)

We present a sample preparation method for measuring magnesium in individual whole lymphocytes by electron probe X-ray microanalysis. We use Burkitt's lymphoma cells in culture as the test sample and compare X-ray microanalysis of individual cells with atomic absorption analysis of pooled cell populations. We determine the magnesium peak-to-local continuum X-ray intensity ratio by electron probe X-ray microanalysis and calculate a mean cell magnesium concentration of 39 +/- 19 mmol/kg dry weight from analysis of 100 cells. We determine a mean cell magnesium concentration of 34 +/- 4 mmol/kg dry weight by atomic absorption analysis of pooled cells in three cell cultures. The mean cell magnesium concentrations determined by the two methods are not significantly different. We find a 10% coefficient of variation for both methods of analysis and a 30% coefficient of variation in magnesium concentration among individual cells by electron ...

Energy Technology Data Exchange (ETDEWEB)

Experimental investigations are presented which demonstrate that the weak ferromagnets are special materials of a larger group of magnets which exhibit two magnetic ordering structures. In weak ferromagnets the main order is antiferromagnetic with a small ferromagnetic component existing in addition. On the other hand, materials in which other combinations of the two basic ordering structures coexist are also known. Common to all these non-collinear spin structures is that the moment components of the two magnetic structures are orthogonal. In the weak ferromagnets this orthogonality manifests already in the paramagnetic phase as a crossover from an isotropic to an anisotropic susceptibility with respect to the applied magnetic field: at high temperatures the antiferromagnetic Curie-Weiss law of the total moment is observed while for T->Tc crossover to a second Curie-Weiss law due to the weak ferromagnetic component occurs. For T->Tc the ferromagnetic ...

Energy Technology Data Exchange (ETDEWEB)

This report covers the progress made on the title project for the project period. Four major areas of inquiry are being pursued. Advanced solid state NMR methods are being developed to assay the distribution of the various important functional groups that determine the reactivity of coals. Special attention is being paid to methods that are compatible with the very high magic angle sample spinning rates needed for operation at the high magnetic field strengths available today. Polarization inversion methods utilizing the difference in heat capacities of small groups of spins are particularly promising. Methods combining proton-proton spin diffusion with {sup 13}C CPMAS readout are being developed to determine the connectivity of functional groups in coals in a high sensitivity relay type of experiment. Additional work is aimed at delineating the role of methyl group rotation in the proton NMR relaxation behavior of coals.

Energy Technology Data Exchange (ETDEWEB)

High-spin states in the neutron-rich nuclei {sup 172,173}Yb have been populated in a {sup 170}Er({sup 7}Li,(p,d,t)xn) incomplete-fusion reaction and the emitted {gamma}-radiation was detected with the GASP array. The signature partners of the 7/2{sup +}[633] rotational band of the odd-N {sup 173}Yb isotope have been newly established and were observed up to spin values of (45/2{sup +}) and (43/2{sup +}), respectively. The ground-state band of the even-even nucleus {sup 172}Yb has been observed up to a spin value of (22{sup +}). No band crossings were found in these bands. To explain this observation, it is proposed that the static pair field is absent, considering that the neutron odd-even mass differences reach for these nuclei very small values and that the band crossing is absent in cranked shell modell calculations without pairing. The results indicate, however, that strong dynamic correlations are still present. ...

International Nuclear Information System (INIS)

Electron spin polarization in excess of 70% has been observed in photoemission from a 0.1 #mu#m-thick epitaxial layer of In_xGa_1_-_xAs with x #approx# 0.13 grown on a GaAs substrate. Under these conditions, the epitaxial layer is expected to be highly strained by the 0.9% lattice mismatch, as confirmed by x-ray diffractometer measurements of the lattice parameter. The electron polarization and the quantum efficiency have been measured as a function of the excitation photon energy from 1.25 to 2.0 eV. A significant enhancement of the electron polarization occurs in the vicinity of 1.33 eV where the expected strain-induced level splitting permits optical excitation of a single band transition. Measurements made on a control sample of 1.14 #mu#m thickness, significantly larger than the critical thickness for pseudomorphic strain, show no polarization enhancement. These measurements represent the first observation of strain-enhanced electron spin ...

Energy Technology Data Exchange (ETDEWEB)

The isotropic and anisotropic hyperfine constants of the ground X/sup 2/..sigma../sup +/ state of /sup 88/SrF and /sup 86/SrF are reported. Vibrational and rotational dependences are studied in a Dunham expansion analysis. Furthermore, the vibrational, rotational, and isotopic dependence of the spin-rotation constant is determined. The following values are obtained for X/sup 2/..sigma../sup +/, ..nu.. = 0, in /sup 88/SrF: ..gamma../sub 0/ = 74.79485 MHz, ..gamma../sub 1/ = 5.752 x 10/sup -5/ MHz, ..gamma../sub 2/ = -6.3 x 10/sup -10/ MHz, b/sub 0/ = 97.0834 MHz, b/sub 1/ = -3.300 x 10/sup -4/ MHz, c/sub 0/ = 30.268 MHz, C/sub I/ = 0.00230 MHz, where ..gamma.. is the spin-rotation parameter, b and c are the Frosch and Foley hyperfine parameters, and C/sub I/ is a nuclear spin-rotation correction. 4 figures, 4 tables.

International Nuclear Information System (INIS)

This article considers a hypothetical imaging device with a spinning slat collimator that measures parallel-planar-integral data from an object. This device rotates around the object 180 deg. and stops at N positions uniformly distributed over this 180 deg. . At each stop, the device spins on its own axis 180 deg. and acquires measurements at M positions uniformly distributed over this 180 deg. . For a fixed total imaging time, an optimal distribution of the scanning time among the data measurement locations is searched by a nonlinear programming method: Nelder-Mead's simplex method. The optimal dwell time is approximately proportional to the weighting factor in the backprojector of the reconstruction algorithm. By using an optimal dwell-time profile, the reconstruction signal-to-noise ratio has a gain of 23%-24% for the filtered backprojection algorithm and a gain of 10%-18% for the iterative algorithms, compared with the situation when a ...

Energy Technology Data Exchange (ETDEWEB)

Differential cross sections for 201.5 MeV proton scattering form /sup 88/Sr were measured. From the analysis of the elastic data, no unique optical-model potential could be obtained, but the radial moments are well determined. In a macroscopic analysis of the collective states it turns out that if the optical potential and transition potential are chosen consistently, unambiguous potential deformation lengths can be obtained even though the optical potential is not unique. Taking into account the range and density dependence of the underlying effective interaction reliable neutron deformation lengths can be obtained. For inelastic transitions of various character microscopic distorted-wave calculations with a density-dependent interaction based on the Paris potential were performed. The nuclear structure was taken from one broken-pair calculations in a large model space, calibrated by (e,e') data. In general a good description is obtained for states with ...

International Nuclear Information System (INIS)

We studied the magnetic dipole moments #mu# of even-odd C isotopes, ranging from proton-rich to neutron-rich nuclei, with antisymmetrized molecular dynamics (AMD). The results are in good agreement with the experimental data. In the "9C ground state the total intrinsic spin of the protons is found to be nonzero (S_p#not =#0), which is unusual in even-odd nuclei. The interesting point is that the spin-orbit force breaks slightly the coupling off of intrinsic spins of the even nucleon group in isospin T=3/2 nuclei. This result is consistent with the newly measured #mu# data that, when combined with "9Li data, indicate an unusual left-angle #sigma# right-angle value larger than unity. A #mu# moment -1.05#mu#_N of "1"7C is theoretically predicted. We also show a good reproduction of E2 transition data. copyright 1996 The American Physical Society.

CERN Document Server

While dealing with molecular systems, it is highly advantageous to work with a basis set which has definite total spin and also belongs to a definite irreducible representation of its symmetry (point) group. But unfortunately, there hadn't been any general simple technique to deal with the problem, especially when molecule possesses non-Abelian point group symmetry. In a previous paper \\cite{sahoo}, we presented a general technique which is a hybrid method based on Valence Bond basis and the basis of z-component of the total spin. The technique is applicable to all types of point groups and is easy to implement on computer. We illustrated the power of the method by applying it to a molecular magnetic system. Here we extend the method to electronic systems and demonstrate this extended technique by applying it to a model icosahedral half-filled electronic system (12 sites). Reasons we took this model are, its a system with huge Hilbert space ...

Energy Technology Data Exchange (ETDEWEB)

Electron paramagnetic resonance (EPR) of coals was considered by using iodine doping technique. Sub-bituminous coal (WA) and bituminous coal (UF) were used to observe EPR spectra using microwaves. With the UF coal, strength of the narrow component of the spectra was found constant regardless of amount of the doped iodine, wherein radicals without interaction with iodine were detected. Strength of the broad component increased with the iodine doping amount, where in deviation of {pi} electrons was detected, which have been generated as a result of interaction between aromatic rings and iodine in the coals. Spin concentration of the WA coal with low coalification degree is constant regardless of the iodine doping amount, and the interaction of the iodine with the aromatic rings was found small. The higher the coalification degree, the more the aromatic ring structure grows, and electron donor capability for the iodine increases. In a system with the entire ...

CERN Document Server

The Hamiltonian structure of the Classical Heisenberg Spin Chain (CHSC) has been extensively studied by a number of authors. First of all, we mention Faddeev and Thaktadjan that, in their fundamental monograph "Hamiltonian Methods in the Theory of Soliton", elucidate the main properties of both continuous and (semi-)discrete models. An analysis of the su(2) continuous model in the context of the reduction theory for Poisson Nijenhuis manifolds was performed by Magri et al in1985, while through a similar approach a few years later Ragnisco and Santini analyzed the discrete case. In the meantime, among the condensed matter community there was some renewed interest on Potts models, sort of generalized spin chains where the relevant field variable is allowed to take values at the $N^{th}$ roots of unity. The proper theoretical setting for such models, at least at the classical level, would have been the extension to NxN matrices of the approach ...

British Library Electronic Table of Contents (United Kingdom)

Abstract Coordination compounds [Ru(acac)2(Q)] (acac=acetylacetonate; Q=o-benzoquinone) were prepared as complexes 1 (Q=o-benzoquinone), 2 (Q=3-methoxy-o-benzoquinone), 3 (Q=4-methyl-o-benzoquinone), and 4 (Q=3,5-di-tert-butyl-o-benzoquinone). The structures of 1 and 2 were determined to reveal a RuIII/o-benzosemiquinone formulation, supported by analysis of experimental data (spectroscopy, magnetism of 1) and by DFT calculations. The S=1 ground state calculated for 1 stands in contrast to the spin-paired analogues with arylimino-o-benzosemiquinonato and diimino-o-benzoquinone ligands. The close contacts of about 5.3- possible between semiquinone O atoms of different molecules in the crystal allow for intermolecular spin-spin interactions and an overall complex magnetic behavior. One quasi...

Energy Technology Data Exchange (ETDEWEB)

A measurement of the magnetic form factor of a ferromagnetic actinide compound of UTe with circularly polarized X-rays is reported. The present geometrical configuration of the measurement gives a form factor of L(k)+0.3S(k), where L(k) and S(k) are the form factors of the orbital and the spin magnetic moment, respectively. We have combined the X-ray magnetic form factor with the neutron one which gives L(k)+2S(k) (G. Busch et al.: J. Phys. C 12 (1979) 1391), and have deduced L(k) and S(k) separately. The obtained profiles of L(k) and S(k) show that the orbital and the spin magnetic moments are spatially spread out more than those calculated for a free uranium ion. (author).